| Sedimentary rock|
Drive from Fayón
| Bajo Aragón-Caspe
Auts ([ˈawts]) is a mountain range west of the Ebro river in the Bajo Aragón-Caspe/Baix Aragó-Casp comarca, Aragon, Spain.
The Auts Range is located about 9 km north of Fayón (Faió), close to the road between Maella and Mequinenza (Mequinensa). The ridge's highest point is Alt dels Auts (Spanish: Alto de los Auts), a 434 m high summit.
The Auts are desolate-looking limestone mountains, smooth, with low and scruffy vegetation and numerous denuded patches. In some documents in the Spanish language, these hills appear under the name Sierra de Mequinenza, but they are actually not a proper "sierra".
The name "Auts" comes most likely from an ancient Catalan word for "heights", "alts" in modern Catalan. Referring to hills this name appears, for example, in Ramon Llull's following text:
«Los cavaliers veem que fant castells i forces en los auts munts, per tal que si son vensuts ni sobrats en los píans, que fugen en los munts».
These moderately high, dry mountains were the scenario of one of the most bloody confrontations during the Battle of the Ebro in the Spanish Civil War (1936–39). On 25 July 1938 the 42nd Division of the Spanish Republican Army successfully crossed the river in this area and occupied the Auts area taking positions in the hills.
Initially the feat of the Republican troops was hailed as a great victory by the Spanish Republic, eager to see a positive outcome of the Battle of the Ebro effort. But the 226th and 227th mixed brigades of the division were soon surrounded and relentlessly massacred in the Auts by General Franco's rebel faction. After having suffered a great number of casualties the few battered survivors of the division had to cross back the Ebro River. There is a monument to the many soldiers who died in the Auts at the feet of the range near the road leading to Mequinensa.